Spanish Albatun Tres is 115 mt long and is the world’s largest tuna purse seiner. Vessels such as this travel from one fish aggregation device (FAD) to another and spread their huge nets to catch everything swimming around the FAD. Around 10% of the catch generated by purse seine FAD fisheries is unwanted bycatch and includes endangered species of sharks and turtles. The catch of large amounts of juvenile bigeye and yellowfin tunas in these fisheries is now threatening the survival of these commercially valuable species. Greenpeace is calling for a total ban on the use of fish aggregation devices in purse seining and the establishment of a global network of marine reserves.